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Full-Text Articles in Life Sciences
Winter Snow Depth In Arctic Alaska Results In Complex Changes In Caribou Forage Quality, Jessica C. Richert
Winter Snow Depth In Arctic Alaska Results In Complex Changes In Caribou Forage Quality, Jessica C. Richert
Electronic Theses and Dissertations
Caribou (Rangifer tarandus) rely on the short growing season for much of their annual nutrition, making them susceptible to even small changes in forage quantity and quality. Body condition in the summer and fall is linked to winter survival rates and fecundity in cows, critical factors in the robustness of caribou populations. Due to a warmer, wetter climate, snowfall is predicted to increase over Alaska’s North Slope in the next several decades. Deeper snow results in higher soil temperatures, allowing microbial mineralization of nitrogen to continue throughout the winter and increasing the availability of nitrogen for plants in spring and …
Heterogeneous Nitrogen Losses: Cost-Effectiveness Analysis Of Changes In Management Across South Dakota, Archibold Quaye
Heterogeneous Nitrogen Losses: Cost-Effectiveness Analysis Of Changes In Management Across South Dakota, Archibold Quaye
Electronic Theses and Dissertations
The loss of nitrogen fertilizer into the atmosphere and waterways is of increasing concern for citizens and policy makers. This is particularly relevant for hypoxia in rivers, lakes, and oceans, but also relevant for policy makers in reducing the increasing concentration of greenhouse gases (GHG) in the atmosphere. GHGs trap heat in the atmosphere and include: carbon dioxide, methane, nitrous oxide and fluorinated gases. Overall, the estimated contribution from the agricultural sector to GHG emissions was 9% in 2013 (EPA, 2013). Further, the addition of nitrogen to the soil through the use of synthetic fertilizers is a main contributor to …
Sagebrush Ecosystem Characterization, Monitoring, And Forecasting With Remote Sensing: Quantifying Future Climate And Wildlife Habitat Change, Collin G. Homer
Sagebrush Ecosystem Characterization, Monitoring, And Forecasting With Remote Sensing: Quantifying Future Climate And Wildlife Habitat Change, Collin G. Homer
Electronic Theses and Dissertations
Sagebrush (Artemisia spp.) ecosystems constitute the largest single North American shrub ecosystem and provide vital ecological, hydrological, biological, agricultural, and recreational ecosystem services. Disturbances continue to alter this ecosystem, with climate change possibly representing the greatest future disturbance risk. Improved ways to characterize and monitor gradual change in this ecosystem are vital to its future management. A new remote sensing sagebrush characterization approach was developed in Wyoming which integrates three scales of remote sensing to derive four primary continuous field components (bare ground, herbaceousness, litter, and shrub), and four secondary components (sagebrush, big sagebrush, Wyoming sagebrush, and shrub …
Measures Of Denitrification In Selected South Dakota Semi-Permanent Prairie Pothole Wetlands, Beverly S. Klein
Measures Of Denitrification In Selected South Dakota Semi-Permanent Prairie Pothole Wetlands, Beverly S. Klein
Electronic Theses and Dissertations
Wetlands are an integral part of agricultural systems in the prairie pothole regions of the North Central United States and Canadian Provinces. Little research has been done on denitrification in prairie potholes, and a better understanding of their denitrifying capability could aide in optimizing management practices near pothole areas. Most probable number (MPN) and denitrifying enzyme activity (DEA or Phase I) assays were conducted. Most probable number (MPN) measures were used to give an estimate of dissimilatory nitrate reduction to ammonia (DNRA) and denitrifying populations present in the wetlands. This study involved 3 selected semi-permanent prairie pothole wetlands near Madison, …